The Colorado AIDS Clinical Trials Unit (ACTU) was established in July 1990 as a subunit of the Harvard ACTU, under the direction of Dr. Robert Schooley. During this period an effective clinical trials infrastructure including clinical personnel, data management, and immunology and virology laboratory support has been developed independent of the Harvard ACTU. Since clinical trials were initiated on August 9, 1990 nearly 100 subjects have been enrolled into ACTG protocols at our site. The rapid accrual of subjects even in the absence of an active recruiting program underscores the enthusiasm of the Colorado HIV-infected community for participation in clinical trials at the only ACTU between St. Louis and San Francisco. We are now requesting support to establish the Colorado ACTU as an independent unit of the AIDS Clinical Trials Group. The Colorado ACTU will emphasize protocols in the areas of primary and opportunistic infection, oncology, and immune based therapy with a focus on studies involving early stages of drug development. The establishment of core laboratories in virology and pharmacology laboratories as components of the Colorado ACTU will enhance our ability to provide intensive laboratory support for the clinical studies proposed in this application. In addition, research projects in the areas of virology, immunology, pharmacology, and opportunistic pathogens are proposed, which will allow us to design and conduct more effective clinical trials in HIV-related disease. These laboratory activities will provide the opportunity to combine basic scientific investigation with carefully conducted clinical trials to expand our understanding of the interactions between HIV and its human host, with a particular emphasis on the role of HIV- and pathogen-specific immunity in the pathogenesis of AIDS.